Today in History is a daily newsletter from Britannica. (more) Today in History—March 7: Rome’s Dual Emperors Written by Andrew Niemchick Andrew Niemchick is a Video Editor and Producer at Encyclopædia Britannica. Andrew Niemchick Fact-checked by Britannica Editors Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree.... Britannica Editors Last updated Mar. 5, 2026 •History On this day in 161, the citizens of Rome scratched their heads at the announcement that they had not one but two new emperors. Today in History is a daily newsletter from Britannica.Encyclopædia Britannica, Inc. Want to learn more about what happened on March 7, or any other day of the year? Sign up to receive the newsletter in your inbox every morning. Upon the death of emperor Antoninus Pius, his heir Marcus Aurelius declared that he...

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